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Sources of non-protein nitrogen and the addition of Sacharomyces cerevisiae to sugar cane based diets for young bulls: intake, digestibility, nitrogen balances and ruminal parameters

The objective of the present study was to evaluate the effects of the non-nitrogenous sources and the addition of Sacharomyces cerevisiae to sugarcane based diets on the intakes and the total and partial apparent digestibilities of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), total carbohydrates (TC), neutral detergent fiber (NDF) and non- structural carbohydrates (NEC). The nitrogen balance and ruminal parameters were also evaluated. Four Holstein-Zebu young bulls rumen and abomasal fistulated were allotted to a 4x4 Latin Square design in a 2 x 2 factorial arrangement. The animals were fed with sugar cane based diets, supplemented with two nitrogenous sources (urea or poultry litter) and two daily Sacharomyces cerevisiae addition (0 and 10 g/anim.). The indigestible neutral detergent fiber (NDFi) was used as a marker, to determine the total and partial apparent digestibilities of the nutrients. The intakes of DM, OM, EE, TC, NEC was not influenced by the nitrogenous sources and by the Sacharomyces cerevisiae addiction. The intakes of CP and NDF were higher for the diets supplemented by poultry litter. The coefficients of total digestibilities of CP and EE were higher for diets with urea. The apparent total digestibilities of DM, OM,TC, and NDF were not influenced by the nitrogenous sources and by the Sacharomyces cerevisiae addiction. The ruminal pH linearly decreased for the diets supplemented with urea, and presented a quadratic response when these diets were combined with Sacharomyces cerevisiae. The ruminal ammonia concentrations presented a quadratic behavior, and the maximum estimated values of 16.90; 26.12; 18.48 and 14.40 mg/dL for the diets with sugar-cane and urea, sugar cane, urea and Sacharomyces cerevisiae; sugar cane and poultry litter; sugar cane, poultry litter and Sacharomyces cerevisiae, respectively.

cattle; dietetic microbes supplements; digestibility; intake


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